Switchable light modulator device comprising polymer structures that create a plurality of cavities that are sealed with a fluid comprising electrophoretic particles

Abstract

A switchable light modulator device ( 201, 202, 203, 204, 205 ) comprises a first substrate ( 101, 102, 103 ) and a second substrate ( 141, 142, 143, 144 ) with opposite major surfaces spaced apart by one or more polymer structures that each comprise two or more parts and define wall features ( 21 b, 22 b, 23 b ) for a plurality of cavities ( 111, 112, 113, 114 ), the cavities sealing a fluid ( 71, 72, 73, 74 ) or gel in discrete volumes. Each of the one or more polymer structures comprises a mould part ( 21, 22, 23 ) bonded to the first substrate and defining a recess ( 31, 32, 33 ), and a cast part ( 81, 82, 83, 84 ) filling the recess and bonded to the second substrate and a surface of the recess, the cast part being defined by the surface of the recess and the second substrate replicating the surfaces of both.

The invention claimed is: 
     
       1. A switchable light modulator device ( 201 ,  202 ,  203 ,  204 ,  205 ) having a first substrate ( 101 ,  102 ,  103 ) and a second substrate ( 141 ,  142 ,  143 ,  144 ) with opposite major surfaces spaced apart by polymer structures that create a plurality of cavities ( 111 ,  112 ,  113 ,  114 ), said cavities sealing a fluid comprising electrophoretic particles,
 wherein the polymer structures include recesses ( 31 ,  32 ,  33 ) that are filled with conducive cast parts ( 81 ,  82 ,  83 ,  84 ), the conductive cast parts being bonded to both the second substrate and a surface of said recess, the conductive cast parts being enclosed by said surface of said recess and said second substrate. 
 
     
     
       2. The switchable light modulator device of  claim 1 , wherein the conductive cast parts comprise a polymer and a conductive filler. 
     
     
       3. The switchable light modulator device of  claim 1 , wherein the polymer structures are optically transparent and the conductive cast parts ( 81 ,  82 ,  83 ,  84 ) obscures light and include a colorant or a light scattering material. 
     
     
       4. The switchable light modulator device of  claim 1 , wherein the recesses ( 31 ,  32 ,  33 ) vary in depth ( 1031 ,  1032 ) or width ( 1041 ,  1042 ). 
     
     
       5. The switchable light modulator device of  claim 1 , wherein the polymer structures additionally include bracing features ( 23   c ). 
     
     
       6. The switchable light modulator device of  claim 1 , wherein the first substrate ( 101 ,  102 ,  103 ) or the second substrate ( 141 ,  142 ,  143 ,  144 ) comprises a flexible transparent material ( 90 ). 
     
     
       7. The switchable light modulator device of  claim 6 , wherein the first substrate ( 101 ,  102 ,  103 ) or the second substrate ( 141 ,  142 ,  143 ,  144 ) additionally comprises a transparent electrode layer ( 60 ). 
     
     
       8. The switchable light modulator device of  claim 1 , wherein the switchable light modulator device ( 201 ,  202 ,  203 ,  204 ,  205 ) has a first state that strongly attenuates light, and a second state that is substantially transparent to visible light. 
     
     
       9. A display, a window, a mirror, a sun shade, or a sign including a switchable light modulator device ( 201 ,  202 ,  203 ,  204 ,  205 ) of  claim 1 .